Key dates in history of National Broadcasting Co.

FILE - In this Friday, Aug. 21, 2009, file photo, the NBC logo glows in neon lights among other iconic signs at its headquarters in New York. Comcast said Tuesday, Feb. 12, 2013, that it's buying General Electric's 49 percent stake in the NBCUniversal joint venture for $16.7 billion several years early, as the company takes advantage of low borrowing costs and what CEO Brian Roberts called a "very attractive price." (AP Photo/Bebeto Matthews, File)

Comcast Corp.'s deal to buy the rest of NBCUniversal would end General Electric Co.'s long ties with the broadcast network. Comcast now owns 51 percent, and GE the remaining 49 percent. Comcast expects to get full ownership by the end of March.

Here's a look at some key events in NBC's history:

1926 — National Broadcasting Co. formed by General Electric Co., Westinghouse Electric Co. and Radio Corporation of America after buying broadcast assets from AT&T. Launches first permanent radio network in United States.

2009 — NBC, fourth in ratings and looking to pare the costs of producing scripted shows, brings Jay Leno to prime time. GE agrees to sell controlling stake in the company to Comcast Corp.

2011 — The Federal Communications Commission and the Justice Department approve Comcast's takeover of NBC Universal with conditions intended to prevent it from keeping NBC programming to itself at the detriment of other cable operators and video websites. NBC Universal loses the space in its name to become NBCUniversal. "Kabletown" replaces GE as the corporate owner on "30 Rock."

2012 — NBC airs the Summer Olympics, held in London. While it expected to take a loss on the coverage given the high costs, it breaks even with ratings up compared with the Beijing Games in 2008. And NBC begins showing clear signs of a comeback, improving ratings after nearly sliding into irrelevancy over the previous decade.

2013 — Comcast announces that it is buying the rest of NBCUniversal from GE for $16.7 billion, doing so years early. "30 Rock" airs its last episode after seven seasons, 14 Emmys and six Golden Globes.